Adding support for the Honeywell HMC5843. The interface to the device is i2c. Signed-off-by: Shubhrajyoti D <shubhrajyoti@xxxxxx> --- drivers/staging/iio/magnetometer/Kconfig | 17 + drivers/staging/iio/magnetometer/Makefile | 5 + drivers/staging/iio/magnetometer/hmc5843.c | 499 ++++++++++++++++++++++++++++ 3 files changed, 521 insertions(+), 0 deletions(-) create mode 100644 drivers/staging/iio/magnetometer/Kconfig create mode 100644 drivers/staging/iio/magnetometer/Makefile create mode 100644 drivers/staging/iio/magnetometer/hmc5843.c diff --git a/drivers/staging/iio/magnetometer/Kconfig b/drivers/staging/iio/magnetometer/Kconfig new file mode 100644 index 0000000..6beda8c --- /dev/null +++ b/drivers/staging/iio/magnetometer/Kconfig @@ -0,0 +1,17 @@ +# +# Magnetometer sensors +# +comment "Magnetometer sensors" + + +config SENSORS_HMC5843 + tristate "Honeywell HMC5843 3-Axis Magnetometer" + depends on I2C && SYSFS +# select INPUT_POLLDEV + help + Say Y here to add support for the Honeywell HMC 5843 3-Axis + Magnetometer (digital compass). + + To compile this driver as a module, choose M here: the module + will be called hmc5843 + diff --git a/drivers/staging/iio/magnetometer/Makefile b/drivers/staging/iio/magnetometer/Makefile new file mode 100644 index 0000000..f9bfb2e --- /dev/null +++ b/drivers/staging/iio/magnetometer/Makefile @@ -0,0 +1,5 @@ +# +# Makefile for industrial I/O Magnetometer sensors +# + +obj-$(CONFIG_SENSORS_HMC5843) += hmc5843.o diff --git a/drivers/staging/iio/magnetometer/hmc5843.c b/drivers/staging/iio/magnetometer/hmc5843.c new file mode 100644 index 0000000..fc3dda9 --- /dev/null +++ b/drivers/staging/iio/magnetometer/hmc5843.c @@ -0,0 +1,499 @@ +/* Copyright (c) 2010 Shubhrajyoti Datta <shubhrajyoti@xxxxxx> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. +*/ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/slab.h> +#include "../iio.h" +#include <linux/types.h> +#include "../sysfs.h" +#include "magnet.h" + +#define HMC5843_I2C_ADDRESS 0x1E + +#define HMC5843_CONFIG_REG_A 0x00 +#define HMC5843_CONFIG_REG_B 0x01 +#define HMC5843_MODE_REG 0x02 +#define HMC5843_DATA_OUT_X_MSB_REG 0x03 +#define HMC5843_DATA_OUT_X_LSB_REG 0x04 +#define HMC5843_DATA_OUT_Y_MSB_REG 0x05 +#define HMC5843_DATA_OUT_Y_LSB_REG 0x06 +#define HMC5843_DATA_OUT_Z_MSB_REG 0x07 +#define HMC5843_DATA_OUT_Z_LSB_REG 0x08 +#define HMC5843_STATUS_REG 0x09 +#define HMC5843_ID_REG_A 0x0A +#define HMC5843_ID_REG_B 0x0B +#define HMC5843_ID_REG_C 0x0C + + +#define HMC5843_ID_REG_LENGTH 0x03 +#define HMC5843_ID_STRING "H43" + +/* + * Range settings in (+-)Ga + * */ +#define RANGE_GAIN_OFFSET 0x05 + +#define RANGE_0_7 0x00 +#define RANGE_1_0 0x01 /* default */ +#define RANGE_1_5 0x02 +#define RANGE_2_0 0x03 +#define RANGE_3_2 0x04 +#define RANGE_3_8 0x05 +#define RANGE_4_5 0x06 +#define RANGE_6_5 0x07 /* Not recommended */ + +/* + * Device status + */ +#define DATA_READY 0x01 +#define DATA_OUTPUT_LOCK 0x02 +#define VOLTAGE_REGULATOR_ENABLED 0x04 + +/* + * Mode register configuration + */ +#define MODE_CONVERSION_CONTINUOUS 0x00 +#define MODE_CONVERSION_SINGLE 0x01 +#define MODE_IDLE 0x02 +#define MODE_SLEEP 0x03 + +/* Minimum Data Output Rate in 1/10 Hz */ +#define RATE_OFFSET 0x02 +#define RATE_5 0x00 +#define RATE_10 0x01 +#define RATE_20 0x02 +#define RATE_50 0x03 +#define RATE_100 0x04 +#define RATE_200 0x05 +#define RATE_500 0x06 +#define RATE_NOT_USED 0x07 + +/* + * Device Configutration + */ +#define CONF_NORMAL 0x00 +#define CONF_POSITIVE_BIAS 0x01 +#define CONF_NEGATIVE_BIAS 0x02 +#define CONF_NOT_USED 0x03 + +static const int regval_to_counts_per_mg[] = { + 1620, /* RANGE_0_7 */ + 1300, + 970, + 780, + 530, + 460, + 390, + 280 /* RANGE_6_5 */ +}; +static const int regval_to_input_field_mg[] = { + 700, + 1000, + 1500, + 2000, + 3200, + 3800, + 4500, + 6500 +}; + +/* Addresses to scan: 0x1E */ +static const unsigned short normal_i2c[] = { HMC5843_I2C_ADDRESS, + I2C_CLIENT_END }; + +/* Each client has this additional data */ +struct hmc5843_data { + struct iio_dev *indio_dev; + u8 rate; + u8 meas_conf; + u8 operating_mode; + u8 range; + s16 data[3]; +}; + +static void hmc5843_init_client(struct i2c_client *client); + +static s32 hmc5843_set_operating_mode(struct i2c_client *client, + u8 operating_mode) +{ + /* The lower two bits contain the current conversion mode */ + return i2c_smbus_write_byte_data(client, + HMC5843_MODE_REG, + (operating_mode & 0x03)); +} + +/* API for setting the measurmet configuration to + * Normal , Positive bias and Negitive bias + */ +static s32 hmc5843_set_meas_conf(struct i2c_client *client, + u8 meas_conf) +{ + struct hmc5843_data *data = i2c_get_clientdata(client); + u8 reg_val; + reg_val = (meas_conf & 0x03) | (data->rate << RATE_OFFSET); + return i2c_smbus_write_byte_data(client, HMC5843_CONFIG_REG_A, reg_val); +} + +static s32 hmc5843_set_rate(struct i2c_client *client, + u8 rate) +{ + struct hmc5843_data *data = i2c_get_clientdata(client); + u8 reg_val; + reg_val = (data->meas_conf) | (rate << RATE_OFFSET); + if (rate >= RATE_NOT_USED) { + dev_err(&client->dev, + "This data output rate is not supported \n"); + return -EINVAL; + } + return i2c_smbus_write_byte_data(client, HMC5843_CONFIG_REG_A, reg_val); +} + +static ssize_t hmc5843_read_measurement(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + /* Return the measurement value from the specified channel */ + struct i2c_client *client = to_i2c_client(dev); + s16 coordinate_val; + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + s32 result; + result = i2c_smbus_read_byte_data(client, HMC5843_STATUS_REG); + while (!(result & DATA_READY)) + result = i2c_smbus_read_byte_data(client, HMC5843_STATUS_REG); + + result = i2c_smbus_read_word_data(client, this_attr->address); + if (result > 0) { + coordinate_val = (int)swab16((u16)result); + return sprintf(buf, "%d\n", + coordinate_val); + } + return result; +} +static IIO_DEV_ATTR_MAGN_X(hmc5843_read_measurement, + HMC5843_DATA_OUT_X_MSB_REG); +static IIO_DEV_ATTR_MAGN_Y(hmc5843_read_measurement, + HMC5843_DATA_OUT_Y_MSB_REG); +static IIO_DEV_ATTR_MAGN_Z(hmc5843_read_measurement, + HMC5843_DATA_OUT_Z_MSB_REG); + +static ssize_t show_operating_mode(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + struct hmc5843_data *data = i2c_get_clientdata(client); + return sprintf(buf, "%d\n", data->operating_mode); +} +static ssize_t set_operating_mode(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + struct hmc5843_data *data = i2c_get_clientdata(client); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + unsigned long operating_mode = 0; + s32 status; + + strict_strtoul(buf, 10, &operating_mode); + dev_dbg(dev, "set Conversion mode to %lu\n", operating_mode); + if (operating_mode > MODE_SLEEP) + return -EINVAL; + + status = i2c_smbus_write_byte_data(client, this_attr->address, + operating_mode); + if (status) + return -EINVAL; + + data->operating_mode = operating_mode; + return count; +} +static IIO_DEVICE_ATTR(operating_mode, + S_IWUSR | S_IRUGO, + show_operating_mode, + set_operating_mode, + HMC5843_MODE_REG); + +static ssize_t show_measurement_configuration(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + struct hmc5843_data *data = i2c_get_clientdata(client); + return sprintf(buf, "%d\n", data->meas_conf); +} + +static ssize_t set_measurement_configuration(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + struct hmc5843_data *data = i2c_get_clientdata(client); + unsigned long meas_conf = 0; + strict_strtoul(buf, 10, &meas_conf); + dev_dbg(dev, "set mode to %lu\n", meas_conf); + if (hmc5843_set_meas_conf(client, meas_conf) == -EINVAL) + return -EINVAL; + data->meas_conf = meas_conf; + return count; +} +static IIO_DEVICE_ATTR(meas_conf, + S_IWUSR | S_IRUGO, + show_measurement_configuration, + set_measurement_configuration, + 0); + +static ssize_t show_rate(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + u32 rate = (i2c_smbus_read_byte_data(client, this_attr->address) & 0x1C) >> RATE_OFFSET; + return sprintf(buf, "%d\n", rate); +} + +static ssize_t set_rate(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + struct hmc5843_data *data = i2c_get_clientdata(client); + unsigned long rate = 0; + strict_strtoul(buf, 10, &rate); + + dev_dbg(dev, "set rate to %lu\n", rate); + if (hmc5843_set_rate(client, rate) == -EINVAL) + return -EINVAL; + data->rate = rate; + return count; +} +static IIO_DEVICE_ATTR(rate, S_IWUSR | S_IRUGO, show_rate, + set_rate, HMC5843_CONFIG_REG_A); + +static ssize_t show_range(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + u8 range; + struct i2c_client *client = to_i2c_client(dev); + struct hmc5843_data *data = i2c_get_clientdata(client); + + range = data->range; + return sprintf(buf, " %dmGa\n", regval_to_input_field_mg[range]); +} + +static ssize_t set_range(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + struct hmc5843_data *data = i2c_get_clientdata(client); + unsigned long range = 0; + + strict_strtoul(buf, 10, &range); + dev_dbg(dev, "set range to %lu\n", range); + + if (range > RANGE_6_5) + return -EINVAL; + + data->range = range; + range = range << RANGE_GAIN_OFFSET; + if (i2c_smbus_write_byte_data(client, this_attr->address, range) == + -EINVAL) + return -EINVAL; + + return count; +} + +static IIO_DEVICE_ATTR(magn_xyz_range, + S_IWUSR | S_IRUGO, + show_range, + set_range, + HMC5843_CONFIG_REG_B); + +static ssize_t show_gain(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + struct hmc5843_data *data = i2c_get_clientdata(client); + return sprintf(buf, "%d\n", regval_to_counts_per_mg[data->range]); +} +static IIO_DEVICE_ATTR(magn_xyz_gain, S_IRUGO, show_gain, NULL , 0); + + +static struct attribute *hmc5843_attributes[] = { + &iio_dev_attr_meas_conf.dev_attr.attr, + &iio_dev_attr_operating_mode.dev_attr.attr, + &iio_dev_attr_rate.dev_attr.attr, + &iio_dev_attr_magn_xyz_range.dev_attr.attr, + &iio_dev_attr_magn_xyz_gain.dev_attr.attr, + &iio_dev_attr_magn_x_raw.dev_attr.attr, + &iio_dev_attr_magn_y_raw.dev_attr.attr, + &iio_dev_attr_magn_z_raw.dev_attr.attr, + NULL +}; + +static const struct attribute_group hmc5843_group = { + .attrs = hmc5843_attributes, +}; + +static int hmc5843_detect(struct i2c_client *client, + struct i2c_board_info *info) +{ + unsigned char id_str[HMC5843_ID_REG_LENGTH]; + + if (client->addr != HMC5843_I2C_ADDRESS) + return -ENODEV; + + if (i2c_smbus_read_i2c_block_data(client, HMC5843_ID_REG_A, + HMC5843_ID_REG_LENGTH, id_str) + != HMC5843_ID_REG_LENGTH) + return -ENODEV; + + if (0 != strncmp(id_str, HMC5843_ID_STRING, HMC5843_ID_REG_LENGTH)) + return -ENODEV; + + return 0; +} + + +static int hmc5843_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct hmc5843_data *data; + int err = 0; + + data = kzalloc(sizeof(struct hmc5843_data), GFP_KERNEL); + if (!data) { + err = -ENOMEM; + goto exit; + } + + /* default settings at probe */ + + data->meas_conf = CONF_NORMAL; + data->range = RANGE_1_0; + data->operating_mode = MODE_CONVERSION_CONTINUOUS; + + i2c_set_clientdata(client, data); + + /* Initialize the HMC5843 chip */ + hmc5843_init_client(client); + + data->indio_dev = iio_allocate_device(); + if (!data->indio_dev) + goto exit_free; + data->indio_dev->attrs = &hmc5843_group; + data->indio_dev->dev.parent = &client->dev; + data->indio_dev->dev_data = (void *)(data); + data->indio_dev->driver_module = THIS_MODULE; + data->indio_dev->modes = INDIO_DIRECT_MODE; + err = iio_device_register(data->indio_dev); + if (err) + goto exit_free; + /* Register sysfs hooks */ + err = sysfs_create_group(&client->dev.kobj, &hmc5843_group); + if (err) + goto exit_free2; + + return 0; +exit_free2: + iio_device_unregister(data->indio_dev); +exit_free: + kfree(data); +exit: + return err; +} + +static int hmc5843_remove(struct i2c_client *client) +{ + struct hmc5843_data *data = i2c_get_clientdata(client); + /* sleep mode to save power */ + hmc5843_set_operating_mode(client, MODE_SLEEP); + iio_device_unregister(data->indio_dev); + sysfs_remove_group(&client->dev.kobj, &hmc5843_group); + kfree(i2c_get_clientdata(client)); + return 0; +} + +/* Called when we have found a new HMC5843. */ +static void hmc5843_init_client(struct i2c_client *client) +{ + struct hmc5843_data *data = i2c_get_clientdata(client); + hmc5843_set_meas_conf(client, data->meas_conf); + hmc5843_set_rate(client, data->rate); + hmc5843_set_operating_mode(client, data->operating_mode); + i2c_smbus_write_byte_data(client, HMC5843_CONFIG_REG_B, data->range); + pr_info("HMC5843 initialized\n"); +} + +static int hmc5843_suspend(struct i2c_client *client, pm_message_t mesg) +{ + hmc5843_set_operating_mode(client, MODE_SLEEP); + pr_info("HMC5843 suspended\n"); + return 0; +} + +static int hmc5843_resume(struct i2c_client *client) +{ + struct hmc5843_data *data = i2c_get_clientdata(client); + hmc5843_set_operating_mode(client, data->operating_mode); + pr_info("HMC5843 resumed\n"); + return 0; +} + +static const struct i2c_device_id hmc5843_id[] = { + { "hmc5843", 0 }, + { } +}; + +static struct i2c_driver hmc5843_driver = { + .driver = { + .name = "hmc5843", + }, + .id_table = hmc5843_id, + .probe = hmc5843_probe, + .remove = hmc5843_remove, + .detect = hmc5843_detect, + .address_list = normal_i2c, + .suspend = hmc5843_suspend, + .resume = hmc5843_resume, +}; + +static int __init hmc5843_init(void) +{ + printk(KERN_INFO "init!\n"); + return i2c_add_driver(&hmc5843_driver); +} + +static void __exit hmc5843_exit(void) +{ + printk(KERN_INFO "exit!\n"); + i2c_del_driver(&hmc5843_driver); +} + +MODULE_AUTHOR("Shubhrajyoti Datta <shubhrajyoti@xxxxxx"); +MODULE_DESCRIPTION("HMC5843 driver"); +MODULE_LICENSE("GPL"); + +module_init(hmc5843_init); +module_exit(hmc5843_exit); -- 1.5.4.7 -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html